Telephone operator Peggy, puts on an act with Matt Wilde at a Bowery amateur night and is seen by Billy Laidlaw, who becomes convinced of her talents. Billy subsequently arranges for the Broadway debut of the act and falls in love with Peggy, who wholeheartedly returns his affection. When the World War breaks out, Billy remains unconcerned until his younger brother is killed in action. Billy then immediately enlists and is sent to France; Peggy joins the Red Cross to be with him, and Grace Laidlaw, Billy's wife, also goes to France, working with the Y. M. C. A. Billy is assigned to destroy an ammunition dump, and Peggy learns, after he has left on the mission, that he has been recalled. The phone lines are down, and Peggy volunteers to go after Billy herself. She is soon faced with having to decide between his life and the lives of a whole battalion. She chooses to sacrifice him and is herself temporarily blinded as a consequence. Peggy is nursed back to health by Grace, who wins her sympathy and respect. When Billy unexpectedly shows up unharmed, Peggy sends him back to his wife, giving up her happiness for that of the couple she has come to love.